Originally Posted by dsbrantjr

I am not familiar with that particular stem, but if it has a single clamping bolt I would find another type. A two bolt stem is better but still has a single point of failure; if one bolt comes loose or breaks the other will not hold reliably. The stems with a 4-bolt clamping means are better in this respect but the bolts must be tightened gradually so that the clamping force is evenly distributed. Carbon assembly compound or coarse valve grinding compound will indeed help hold the adjustment with less bolt torque, I think it would be worth a try.